How long to seed biomedia?

[solitude127]

I'm trying to seed some Seachem Matrix by soaking it in my established tank, how long should it be left in the sump of the established tank before it's considered "seeded"?

 

[EeyoreIsMySpiritAnimal]

I'm trying to seed some Seachem Matrix by soaking it in my established tank, how long should it be left in the sump of the established tank before it's considered "seeded"?

Depends on what you want it to do. For basic ammonia and nitrite processing, maybe a week or so if it's in an area with adequate flow. For denitrifying, it will take quite a bit longer for the anaerobic bacteria to colonize.